In particular in the course of ore extraction or in the area of scrap separation, it is often intended to separate particles of different magnetic properties from one another, in particular magnetizable particles from non-magnetizable particles. It has been proposed for this purpose to arrange one or more permanent magnets near a separating channel, which is defined for example by a tube, in order to generate a magnetic field gradient inside the tube. Then a suspension which contains the magnetizable particles and non-magnetizable particles is passed through the separating channel. On account of the prevailing magnetic field gradients, the magnetizable particles are subjected to the action of forces that are also in a scalar relationship with the field strength and deflect them particularly toward the side wall of the separating channel that is adjacent to the permanent magnet.
Continuous processes in which the laterally separated magnetizable particles are to be separated from the non-magnetic particles by a separating device, for example a screen, have been proposed, but the force distribution in the separating channel is then usually so inhomogeneous that deposits form on the walls. It is therefore often customary to provide magnetic field gradients and magnetic fields of a strength that leads to the accumulation of the magnetizable fraction on the walls of the separating channel, so that it can be removed in a subsequent flushing step.
However, the magnetic field gradients/field strengths generated by such an arrangement are disadvantageously too small in extensive areas of the separating channel to ensure an effective separation.